1. Field of the Invention
The present invention relates to a disc drive suspension incorporated in an information processor, such as a personal computer.
2. Description of the Related Art
A hard disc drive (HDD) that is used to record in or read data from a rotating disc has a disc drive suspension on the distal end portion of an actuator arm. A head section that includes a slider is provided on the distal end portion of the suspension. When the disc rotates, the slider slightly lifts above the surface of the disc, whereupon an air bearing is formed between the disc and the slider.
The disc drive suspension comprises a load beam section, a flexure fixed thereon, etc. The slider is mounted on the distal end of the flexure. There are flexures of various forms that are based on required specifications. One such flexure is described in U.S. Pat. No. 5,796,552.
A wiring portion 1 of a conventional wired flexure shown in FIG. 10 includes a metal base 2 formed of a thin stainless-steel sheet, an insulating layer 3 formed of polyimide on the metal base 2, a pair of write conductors W1 and W2 and a pair of read conductors R1 and R2 extending along the insulating layer 3, etc. The respective one ends of the write conductors W1 and W2 and the read conductors R1 and R2 are connected electrically to terminals (e.g., MR element terminals) of the slider. The respective other ends of the write conductors W1 and W2 and the read conductors R1 and R2 are connected electrically to write and read electric circuits (not shown).
As write current flows through the write conductors W1 and W2, some of its energy may possibly be induced in the read conductors R1 and R2. As shown in FIG. 10, for example, an electric or magnetic field (indicated by electric force lines F) that is generated in the write conductors W1 and W2 exerts a greater influence on the read conductor R1 that is located closer to the write conductors W1 and W2 than on the other read conductor R2. Thus, a greater induced electromotive force is generated in the one read conductor R1 than in the other read conductor R2, so that a potential difference is caused between the read conductors R1 and R2.
The potential difference arouses the problem of cross talk. Depending on its level, cross talk may deteriorate or even ruin an MR element of the head section and the like. With the increase of the recording density of modern discs, in particular, the head section is liable to be susceptible to cross talk. Therefore, cross talk should be minimized.
The difference between the influences of the electric or magnetic field in the write conductors W1 and W2 on the read conductors R1 and R2 can be reduced by increasing a distance S from the write conductors W1 and W2 to the read conductors R1 and R2. Thus, if the distance S can be increased, influences of the write conductors W1 and W2 on the read conductors R1 and R2 are reduced, so that the difference in potential between the read conductors R1 and R2 is lessened.
However, the wiring portion 1 is restricted in size and its width is expected to be reduced these days, in particular, so that it is hard to increase the distance S. In the disc drive suspension of which the wiring portion must be narrowed, therefore, the cross talk characteristic sometimes must inevitably be neglected in some measure.